U.S. Pat. Nos. 4,091,036, issued May 23, 1978, 4,094,840, issued June 13, 1978, 4,133,811, issued Jan. 9, 1979, and 4,146,538, issued Mar. 27, 1979, each discloses androstene intermediates having the partial structural formula ##STR2## wherein R.sub.a is alkyl or aryl, and both R.sub.a groups are the same.
U.S. Pat. No. 4,361,559, issued Nov. 30, 1982, discloses androstene-17-dithioketals having the partial structural formula ##STR3## wherein R.sub.b and R.sub.c are the same or different and each is alkyl, cycloalkyl, or aryl; R.sub.d is hydrogen, hydroxy, alkoxy, aryloxy, alkylthio, arylthio, ##STR4## or halogen; and the broken line in the 15,16-position represents the optional presence of ethylenic unsaturation. The steroids have antiinflammatory activity.
U.S. Pat. No. 4,447,426, issued May 8, 1984, discloses androstene-17-dithioketals having the partial structural formula ##STR5## wherein one of R.sub.e and R.sub.f is alkyl, cycloalkyl, aryl, arylalkyl or --CH.sub.2 X wherein X is alkylthio, alkoxy, aroyloxy, alkanoyloxy or alkoxycarbonyl and the other is alkylthioalkyl, alkoxyalkyl, alkanoyloxyalkyl, aroyloxyalkyl, alkoxycarbonylalkyl, carboxylalkyl or arylalkyl; R.sub.g is hydrogen, hydroxy, alkoxy, aryloxy, oxo, methylene, alkylthio, arylthio, alkanoyl, alkanoyloxy, or halogen; and the broken line in the 15,16-position represents the optional presence of ethylenic unsaturation. The steroids have antiinflammatory activity.
U.S. Pat. No. 4,435,326, issued Mar. 6, 1984, discloses androstene-17-dithioketals having the partial structural formula ##STR6## wherein R.sub.h is hydrogen and R.sub.i is alkyl, cycloalkyl, aryl, arylalkyl, alkylthioalkyl, alkoxyalkyl, alkanoyloxyalkyl, aroyloxyalkyl, alkoxycarbonylalkyl, carboxyalkyl, or arylalkyl, or R.sub.h is alkanoyl or aroyl and R.sub.i is alkyl; and R.sub.j is hydrogen, hydroxy, alkoxy, aryloxy, oxo, methylene, alkylthio, aryltiho, alkanoyl, alkanoyloxy, or halogen. The steroids are useful intermediates for preparing steroids with antiinflammatory activity.
U.S. Pat. No. 4,427,592, issued Jan. 24, 1984, discloses androstene-17-dithioketals having the partial structural formula ##STR7## wherein one of R.sub.k and R.sub.m is alkyl, aryl, arylalkyl, or cycloalkyl, and the other is alkenyl, substituted alkenyl, alkynyl, substituted alkynyl, mono-, di- or trifluoroalkyl, cyanoalkyl, alkanoylalkyl or ##STR8## wherein R.sub.p and R.sub.q are the same or different and each is hydrogen or alkyl.